Fluid cooling device

ABSTRACT

The invention relates to a fluid cooling device ( 1 ) as a structural unit having a drive motor ( 2 ) which drives a rotatable fan impeller ( 3 ), and having a storage tank ( 4 ) which has a filling opening ( 6 ) as well as a fill-level indicator ( 7 ) and from which at least one fluid can be conveyed into a hydraulic working circuit, wherein in the hydraulic working circuit the fluid is heated and is cooled via a heat exchanger ( 5 ) of the structural unit, and preferably returned into the storage tank ( 4 ). The invention is characterised in that the structural unit is designed as a turning assembly in which the filling opening ( 6 ) for fluid and the fill-level indicator ( 7 ) are disposed on the storage tank ( 4 ) in such a way that they can be used and Mad in the case of a first, preferably vertical installation direction (X, Y) of the structural unit, and in the case of a second installation direction (Y, X) which is inclined with respect to the fast installation direction (X, Y), preferably at right angles thereto.

The invention relates to a fluid cooling device as a structural unit having a drive motor which drives a rotatable fan impeller, and having a storage tank which has a filling opening and a fill-level indicator and from which at least one fluid can be conveyed into a hydraulic working circuit, wherein in the hydraulic working circuit the fluid is heated and cooled via a heat exchanger of the structural unit, and preferably can be returned again to the storage tank.

Fluid cooling devices as part of compact hydraulic assemblies or as a functional unit for a hydraulic working circuit are fundamentally known. They generally consist of a cooling device consisting of a radiator with a fan blower and a storage tank which is attached to it for a circulating fluid. Such fluid cooling devices are used both stationary and in mobile applications in motor vehicles, in particular commercial vehicles or heavy machinery, in which additional hydraulic circuits can be temporarily used.

DE 103 28 177 A1 describes a fluid cooling device as a modular structural unit with a drive motor which drives a fan blower and a pressurized fluid pump. A fluid (hydraulic oil) is conveyed out of a storage tank into a hydraulic working circuit with at least one consumer. The pressurized fluid is heated in the hydraulic working circuit in the operation of the latter and is cooled again via a cooling device before it travels again into the indicated storage tank. The storage tank generally comprises the fan blower or fan impeller in the manner of a flow guidance apparatus or in the form of a so-called NACA ring, as a result of which on the one hand an improved blower flow and on the other hand a damping action of operating noise of the fan blower are effected. Moreover, the mechanical measures reduce the number of components and the installation effort for this fluid cooling device.

Furthermore, WO 98/42986A1 describes a fluid cooling device which forms a compact structural unit consisting of a motor which drives a fan impeller and a fluid pump. In the hydraulic working circuit in turn the fluid is heated by flow losses and adiabatic processes and is routed to a heat exchanger. The fluid is returned again from the fluid cooling device to the oil tank. The oil tank is made trough-shaped with walls which partially reshape the motor and the fluid pump. The illustrated fluid cooling device constitutes a compact design which manages without pipe connections so that the structural unit consisting of a filter and pump unit as well as a cooling unit can be connected in a space-saving manner to an oil tank without further piping.

However, the fluid cooling devices which have been described here only by way of example and which are readily available on the market are special solutions which have been developed and adapted more or less specifically for certain installation situations on site and which do not allow, for example, a different spatial arrangement, for instance as a turning assembly. Their concept, the type and arrangements, especially of fluid ports and filling openings or fill-level indicators, define a fixed installation situation in their mechanical environment which in this respect cannot be changed.

Proceeding from this prior art, the object of the invention is in turn to further improve the known solutions while maintaining their advantages, such that the fluid cooling device enables different installation directions and yet is structurally simple, especially with respect to its components, such as the filling opening, the fill-level indicator, and the pertinent fluid ports.

This object is achieved by a fluid cooling device with the features of claim 1 in its entirety.

In that, according to the characterizing part of claim 1, the structural unit (fluid cooling device) is made as a turning assembly in which a filling opening, preferably provided with a filter device, and a fill-level indicator are located on the storage tank such that the structural unit can be installed in at least two installation directions, preferably according to two major axes and preferably in a vertical installation direction and in a horizontal installation direction which is located at a right angle to the vertical direction, a structural measure is devised for installing the fluid cooling device in different installation positions and still managing with a minimum number of fill-level indicators and filling openings, specifically preferably with only one indicator or opening at a time. Preferably, it is therefore provided that the fluid cooling device be installed accordingly in at least two different installation positions on a third component with a single filling opening and with a single fill-level indicator which are made correspondingly, without operational failures.

In order to enable proper filling of the storage tank with fluid and in order to be able to read the fill level regardless of the installation position of the fluid cooling device, whether in the direction of a vertical major axis or in the direction of an axis which intersects it, it is provided that the filling opening and the fill-level indicator are arranged in a corner region of the storage tank. The pertinent corner region is characterized by a flattening of the pertinent corner of the storage tank, that is, by a removal of the corner formed by the three wall surfaces which are otherwise tapered toward one another. Instead of the indicated corner, a wall or a corner surface is formed which intersects all three pertinent wall surfaces at roughly 45° and which enables the arrangement of the filling opening at the apex of the boundary lines of the individual wall surfaces of the storage tank. The storage tank preferably has a cuboid-like shape with edges which run roughly parallel to one another on the individual side surfaces which are roughly the same length in one preferred embodiment.

Adjacent to the filling opening, which can also be equipped with a filter device and a pressure equalization apparatus, there is the fill-level indicator. The fill-level indicator is preferably formed by scaling which is made directly and preferably integrally with the wall of the storage tank. The scaling is located around a check opening or check indicator (inspection-glass) which is recessed in the wall of the storage tank. The storage tank is preferably a thermoplastic tank which is formed in a forming method or blow molding method so that the scaling in the form of spaced graduation marks can be done at the same time in the production of the storage tank.

Instead of spaced graduation marks, however, only ever one individual fill-level mark at a time can also be provided which, for example, shows a maximum or minimum fill-level height in the storage tank, with the scaling or the individual graduation mark indication including a right angle with the pertinent second scaling or the second individual graduation mark indication. Otherwise, the scaling can be obtained by a corresponding shaping within a deep drawing mold or blow mold for the production of the storage tank.

Preferably, the walls of the storage tank are made transparent so that the fill level can be directly read on the scaling used. In order to effect UV radiation shielding for the pertinent fluid, it can be feasible to form the storage tank from a milky-cloudy plastic or from a nontransparent plastic so that the fill level can advantageously be read at the same time on a transparent sealing element which closes the check opening in the form of an inspection glass in whose adjacent wall region the respective scaling is again located in order to be able to adjust the fill level between the amount which is shown in the inspection glass and the adjacent scaling.

In one preferred embodiment, the sealing element need not be made transparent if the wall of the storage tank is transparent. If, however, the wall of the storage tank is not transparent, it is recommended that a transparent sealing element be used for the check opening in the form of the inspection glass. There can also be partial transparency for the wall of the storage tank such that checking of the balancing between the scaling and the fill-level height in the storage tank is still enabled.

In order to protect against damage, the fill-level indicator can be inserted in a depression of the wall outline of the storage tank. The scaling includes preferably an imaginary angle of 90° to one another in a corresponding arrangement directly adjacent around the check opening.

The storage tank is used as a support for the fan impeller together with the drive motor and surrounds said fan impeller preferably as a frame so that a fluid-filled box structure around the rotatable fan impeller is implemented. The storage tank and its shape can be chosen such that on the one hand it can be used as a guide apparatus for inflowing air and on the other hand forms a good damping measure for possible operating noise of the fan impeller. Cooling air preferably flows through the storage tank, and the heat exchanger through which the heated fluid flows can likewise be an integral component of the storage tank, it preferably encompassing the heat exchanger at least on two opposite sides and securing it on a box construction or frame construction of the storage tank.

Advantageously the heat exchanger is integrated into the outline of the storage tank such that overall a cuboid or a cuboid-like shape of the fluid cooling device as a structural unit arises which in this respect manages without noteworthy attachment parts and projections for mounting on third components.

A pressure relief valve of the fluid cooling device adjacent to the filling opening and the fill-level indicator can likewise be a component of the storage tank. In this context, the operation of the fluid cooling device also would become possible without any reservation by changing the installation position, based on considerations related to safety engineering, owing to the pressure relief valve.

It can furthermore be advantageous to make the different fluid ports on the storage tank or the fluid cooling device rearrangeable for matching to technical specifications of the hydraulic working circuit. This in turn promotes the overall modular structure of the fluid cooling device with its components.

The fluid cooling device according to the invention is detailed below using one exemplary embodiment according to the drawings. The figures are schematic and not to scale.

FIG. 1 shows a perspective view of a fluid cooling device according to the invention;

FIG. 2 shows a view of the fluid cooling device according to FIG. 1 in the vertical installation direction;

FIG. 3 shows a view of the fluid cooling device according to FIG. 1 in the horizontal installation direction by the fluid cooling device being pivoted by a pivot angle of 90° clockwise in the direction of looking at FIG. 1;

FIG. 4 shows a perspective view of one installation example of the fluid cooling device in a vehicle frame in the vertical installation direction;

FIG. 5 shows a rear view of the fluid cooling device with a view of the heat exchanger in the form of a finned radiator which is integrated in the storage tank of the fluid cooling device; and

FIG. 6 shows a view of the lower or bottom side of the fluid cooling device viewed from underneath.

FIG. 1 shows in a perspective, schematic view a fluid cooling device 1 for holding and cooling a fluid which can be introduced into a hydraulic working circuit of a commercial vehicle (not shown). The fluid can be a hydraulic oil for a connectable, hydrostatic, or mechanical transmission of the motor vehicle. The fluid cooling device 1 can also be integrated into existing hydraulic drive circuits of propulsion machinery or machine tools in order to cool the corresponding working hydraulic oil.

FIGS. 2 and 3 shows two possible installation positions of the fluid cooling device 1, with the installation position in FIG. 2 showing a substantially vertical alignment of the fluid cooling device 1 and the alignment according to FIG. 3 showing a horizontal arrangement of the fluid cooling device 1. In this respect, the vertical installation configuration according to FIG. 2 corresponds to the installation situation according to FIG. 4 and, for the horizontal arrangement according to FIG. 3, the fluid cooling device 1, which is shown in FIGS. 1 and 5, would be shown tilted into or out of the plane of the figure around the axis of incline by 90° respectively.

Essential components of the fluid cooling device 1 are a storage tank 4, which describes the shape of the fluid cooling device 1, a drive motor 2, for example, in the form of a direct current electric motor, and a fan impeller 3 which is driven by the motor (see FIG. 5). Free side surfaces of the shape of the fluid cooling device 1, defined overall by a cuboidal shape of the storage tank 4, are used to secure the fluid cooling device 1.

FIG. 1 furthermore shows a front view of the fluid cooling device 1, with the storage tank 4 for fluid, formed in a rotation blow molding method from preferably polyethylene plastic, offering a substantially rectangular front view to the viewer. The drive motor 2, which is suspended as a hub motor in a round blower opening 16 roughly in the center of the storage tank 4 and which drives a five-blade fan impeller 3, in operation produces a cooling air flow in the direction of looking at FIGS. 1, 4, and 5 in the parallel direction through the blower opening 16.

Fins 17, which extend radially from the drive motor 2 and which run in the manner of bridges to the edge of the blower opening 16, can be used as a kind of rectifier for smoothing of the coolant air flow and in this way also stiffen the respective cover grating 18 for the fan impeller 3. Depending on the execution of the fan impeller, the flow direction of the cooling air through the blower opening 16 could also be provided inversely, in particular, if certain installation situations of the fluid cooling device 1 should require this. An inverse flow air reversal can likewise also be achieved by an inverse direction of rotation of the blades in fan operation. The storage tank 4 has a conically tapering shape in the form of an inlet funnel to the blower opening 16 which is closed by the cover grating 18 so that inlet losses for the blower are small and in this respect the flow characteristic of the cooling air through the storage tank 4 is favorable.

Viewed in the direction of looking at FIG. 1, the storage tank 4 on its right side wall has a bevel 29 which constitutes a custom feature and may also result from the respective installation situation for the fluid cooling device 1. On the right lower side, viewed in the direction of looking at FIG. 1, on the front wall which is muted around the blower opening 16, there are different connecting pieces 19 for the leakage oil supply from the hydraulic working circuit which is not detailed. Furthermore, there are different U-shaped grooves which are routed vertically and horizontally, viewed in the direction of looking at FIG. 1, and which can facilitate positive securing in position on a support or on chassis parts of the motor vehicle structure and otherwise stiffen the tank construction. This also yields correspondingly large contact surfaces which are separated from one another for securing of the storage tank 4 on third components.

As FIG. 5 furthermore shows, the blower air flow is muted centrally onto the cooling fins 20 of a heat exchanger 5 which run horizontally in FIG. 5. The cooling This 20 extend at the same distance to one another from a box-shaped inlet distribution channel 21 to a likewise box-shaped outlet channel 22 which diverts cooled fluid back into the interior of the storage tank 4. The channels 21, 22 are located perpendicular to the cooling fins 20, and the entire heat exchanger 5 can be made both as a casting and also in a sheet metal construction with solder or weld connections.

The heat exchanger 5 has a pressure relief valve 14, which is installed on one upper side of the inlet distribution channel 21 and which discharges in the region of an upper side wall 10″ (compare FIG. 1) of the storage tank 4. In order to enable installation of the fluid cooling device 1 in the two installation directions X, Y which are perpendicular to one another, there is a filling opening 6 on the upper left corner region 8, viewed in the direction of looking at FIG. 1, on the fluid cooling device 1 which consists of a filler stub 23 with an external thread onto which a sealing cover 24 with knurling is screwed. The indicated corner region is defined by a wall surface which in a plan view is triangular and connects side walls 10, 10′, 10″ of the storage tank 4 to one another. Within the sealing cover 24, a filter element, which is not detailed, can be integrated in the conventional manner.

The wall surface 9 is made integral with the other walls of the storage tank 4. Adjacent to the filling opening 6, there is a fill-level indicator 7 on the side wall 10″, which is shown in FIG. 1 as the top of the storage tank 4, and it consists of a round fill-level check opening 13 in the form of an inspection glass and two scalings 11,11′ which assume a right angle to one another. The respective scaling 11,11′ can consist of an individual mark indication according to this embodiment, which provides the viewer an indication of the desired maximum or minimum volumetric level in the storage tank 4, or consist of a multiple mark arrangement which allows a conclusion about which defined amount is held in the storage tank 4. In the embodiment as shown in FIGS. 2 and 3, there is one scaling 11 parallel to the installation direction X, and the other scaling 11′ is parallel to the mounting installation direction Y.

The point S of intersection of the two scaling regions 11, 11′ forms the midpoint of the fill-level check opening 13. The fill-level check opening 13 (inspection glass) is spaced at a distance from the filling opening 6 by roughly ⅛ to ⅕ of the total length or total width of the storage tank 4. The respective position of the check opening 13 in conjunction with the respective scaling 11, 11′ is dependent on which fill level is dictated for the respective storage tank 4 on the user side. A sealing element 12 in the form of a clipped-in plastic cap seals the fill-level check opening 13, and the sealing element is made transparent in the illustrated exemplary embodiment so that the fluid level can also be read on the sealing element 12.

As FIGS. 2 and 3 show in a respective plan view of the side wall 10″, the heat exchanger 5 is located off-center with its pressure relief valve 14 on the storage tank 4 and, viewed with reference to all side walls of the storage tank 4, is integrated roughly flush into the cuboid-like overall shape of the tank 4. The cooling fins 20 (see FIG. 5) have a rectangular, strip-like plan shape with uniform width and thickness over their entire length. The heat exchanger 5 is made modular as an independent component and can be connected to the storage tank 4 to carry fluid via plug connections without piping. This yields a very quick and simple overall installation option.

As FIG. 5 in a rear view of the heat exchanger 5 shows, it is connected to the storage tank 4 on its inlet distribution channel side 21 with screws on two clips 25. On the side of its outlet channel 22, the heat exchanger 5 is inserted into undercuts of the storage tank 4 in a positive, detachable manner. There can likewise be a positive, detachable connection of the heat exchanger 5 in addition on its inlet distribution channel side 21 so that overall installation is simple and the heat exchanger 5 is in extensive surface connection to the storage tank 4.

The storage tank 4 with its components, due to its manner of production manufactured as a plastic part in a blow molding or rotation molding method, can be such that not only are there mechanical and hydraulic connection options, but also cable guides for cable sets of the electric drive motor 2. Thus, in FIGS. 1 to 3, there is a gap 26 for cable routing located approximately in the middle on an edge of the side wall 10″, which edge is adjacent to the grating 18 for the fan impeller 3. The power supply for the drive motor 2 can be carried out in the indicated manner through the gap 26.

FIG. 6 in turn shows a view of the bottom of the fluid cooling device 1 together with that side from which the fluid is taken from the storage tank 4. For this purpose, on a wider corner region 27 of the tank 4, there is a removal opening 28 which can have a corresponding fluid coupling. The removal opening 28, similarly to the wall surface 9, is located in the intersection region of three side surfaces of the storage tank 4 and is located diagonally opposite the wall surface 9 on the storage tank 4. The position of the removal opening 28 makes it possible for the removal opening 28 to come to rest at the lowest point of the storage tank 4 in the two intended installation positions of the fluid cooling device 1. Likewise, FIG. 6 shows a view of the return connecting piece 15 for fluid which is routed from the hydraulic working circuit back to the heat exchanger 5. This return connecting piece 15 is located on the bottom of the box-shaped inlet distribution channel 21. 

1. A fluid cooling device (1) as a structural unit having a drive motor (2) which drives a rotatable fan impeller (3), and having a storage tank (4) which has a filling opening (6) and a fill-level indicator (7) and from which at least one fluid can be conveyed into a hydraulic working circuit, wherein in the hydraulic working circuit the fluid is heated and cooled via a heat exchanger (5) of the fluid cooling device (1), and preferably can be returned again to the storage tank (4), characterized in that the structural unit is made as a turning assembly, in which the filling opening (6) for fluid and the fill-level indicator (7) are located on the storage tank (4) such that the indicator can be used or read in a first preferably vertical installation direction (X, Y) of the structural unit and in a second installation direction (Y, X) of the structural unit which is tilted relative to the first installation direction (X, Y) and which is provided preferably at a right angle to it.
 2. The fluid cooling device according to claim 1, characterized in that the filling opening (6) and the fill-level indicator (7) are located in a corner region (8) of the storage tank (4).
 3. The fluid cooling device according to claim 1 or 2, characterized in that the filling opening (6) is located on a wall surface (9) of the storage tank (4), which surface connects three side walls (10, 10′, 10″) of the storage tank (4) in the corner region (8) to one another.
 4. The fluid cooling device according to claim 1, characterized in that the fill-level indicator (7) is formed by scaling (11, 11′) which can be read in at least two installation directions (X, Y), which is located on the outside of one side wall (10″) of the storage tank (4), and which is located in the region of a fill-level check opening (13) which is sealed with a sealing element (12).
 5. The fluid cooling device according to claim 1, characterized in that the fill-level indicator (7) is located countersunk in the outline of the storage tank (4) and the sealing element (12) is made non-transparent in a transparent execution of the side wall (10″) of the storage tank (4) and is made transparent in a non-transparent execution of the side wall (10″) of the storage tank (4).
 6. The fluid cooling device according to claim 1, characterized in that the filling opening (6) is located in one corner region (8) of the storage tank (4) which is defined by a tilted triangular wall surface (9) which passes into the three side walls (10, 10′, 10″) which rest substantially vertically on top of one another.
 7. The fluid cooling device according claim 1, characterized in that one installation direction (X) runs parallel to the side wall (10′) which encompasses the fan impeller (3) on the face side, and that the other installation direction (Y) is located parallel to the side wall (10″) with the fill-level indicator (7).
 8. The fluid cooling device according to claim 1, characterized in that the heat exchanger (5) is inserted into the outline of the storage tank (4) and is enclosed at least on two sides by the storage tank (4).
 9. The fluid cooling device according to claim 1, characterized in that there is a pressure relief valve (14) of the structural unit adjacent to the filling opening (6) and the fill-level indicator (7).
 10. The fluid cooling device according to claim 1, characterized in that for fluid flowing out of the hydraulic working circuit into the structural unit a return connecting piece (15) is located rearrangeably on the latter. 